<template>
	<div>
		<router-link tag="div" to="/" class="header-abs" v-show="showAbs">
			<div class="iconfont header-abs-back">&#xe624;</div>
		</router-link>
		<div class="header-fixed" v-show="!showAbs" :style="opacityStyle">
			<router-link to="/">
				<div class="iconfont header-fixed-back">&#xe624;</div>
			</router-link>
			景点详情
		</div>
	</div>
</template>

<script>

export default {
  name: 'DetailHeader',
  data () {
	return {
		showAbs: true,
		opacityStyle: {
			opacity: 0
		}
	}
  },
  methods: {
	handleScroll () {
		const top = document.documentElement.scrollTop
		if (top > 60) {
			let opacity = top / 140
			opacity = opacity > 1 ? 1 : opacity
			this.opacityStyle = { opacity }
			this.showAbs = false
		} else {
			this.showAbs = true
		}
	}
  },
  activated (){
	window.addEventListener('scroll',this.handleScroll)
  }
}
</script>

<style lang="stylus" scoped>
	@import '~styles/varibles.styl'
	.header-abs
		position: absolute
		left: .2rem
		top: .2rem
		width: .8rem
		height: .8rem
		line-height: .8rem
		border-radius: .4rem
		text-align: center
		background: rgba(0, 0, 0, .8)
		.header-abs-back
			color: #fff
			font-size: .4rem
	.header-fixed
		z-index: 2
		position: fixed
		top: 0
		left: 0
		right: 0
		height: $headerHeight
		line-height: $headerHeight
		text-align: center
		color: #fff
		background: $bgColor
		font-size: .32rem
		.header-fixed-back
			position: absolute
			top: 0
			left: 0
			width: .64rem
			text-align: center
			font-size: .4rem
			color: #fff
</style>
